The present invention relates to the easy installation and safe operation of a residential garage or hinged panel "overhead" door of the general style and type as earlier disclosed by two (2) patents issued to K. E. Johanson: U.S. Pat. No. 2,015,402, 9/1935 and U.S. Pat. No. 2,568,808, 9/1951.
Conventional installation of hinged panel overhead door requires a garage opening with plumb vertical jambs and a level header, work normally done by a competent construction carpenter. The installer checks the opening, which must be the same size as the door, and mounts various components of bottom section hardware on the vertical jambs and the garage ceiling behind the header. The hardware includes mounting brackets, rollers, hinges, two vertical and horizontal metal roller guide tracks, left hand and right hand, and the laterally hinged panels, four or five, of the door.
In conventional installations, the multiple hinged panels closing the garage opening are counter-balanced during opening and closing movement relative to the roller guide tracks by strong springs. The most recent counter-balance systems known to the inventor use either dual extension springs mounted above the left and right hand horizontal tracks or torsion springs mounted on the level header above the door opening.
It is known to the inventor and others familiar with the garage door industry that a counter balance system with torsion springs mounted on the level header above the door opening require that the original or professional door installer use special lever bars for adjusting door balance during opening and closing movement. Typically, accidents occur where homeowners decide to adjust or replace torsion springs as a Do-It-Yourself (DIY) home improvement project. Few homeowners have access to the special lever bars used by the professional. Such a bar is a 24" to 36" length of tempered steel that inserts through round openings in journal sleeves attached to the ends of the springs. A homeowner will often use a screwdriver. In most cases, accident victims grossly underestimate the resultant torque of the springs being wound by turning of a journal sleeve and could lose control of the screwdriver.
The inventor has determined that installation, operation and homeowner routine maintenance of a hinged panel overhead garage door will be improved by having an opening-closing or door raising and lowering mechanism which is mounted laterally along the upper most or top door panel. The opening-closing mechanism will have an integrally associated electric motor and gear reduction drive component located mediate of and for a direct reaction with opposed vertical and horizontal gear and roller guide tracks. It has been further determined that a specific curvature for opposed guide tracks in the area of transition movement of door panels from vertical to horizontal is to be preferred.